Tuesday's report, which has a two month lag, shows local values in October were 4.5 percent lower when compared to October 2010 and down 0.6 percent when compared to September.

Atlanta, which posted the biggest year-over-year drop, and the Midwest "really stand out in terms of recent relative weakness," said David M. Blitzer, S&P's chairman of the index committee, in a statement.

Meanwhile, Detroit and Washington, D.C. were the only two areas that posted year-over-year gains, at 2.5 percent and 1.3 percent respectively. Phoenix was the sole city that saw an increase when comparing October to September, at 0.3 percent.

On a national level, Case Shiller analysts say average home prices in October have returned to mid-2003 levels and are about 31 percent to 32 percent off from their peak in the summer of 2006.

Here's an analysis from Patrick Newport, an economist from IHS Global Insight:

"Home prices are falling after stalling earlier this year ... The stall earlier this year probably resulted from a slowing of the foreclosure pipeline after the media reported that lenders had cut corners in processing foreclosures."

The Case-Shiller index tracks changes in the value of homes nationally and in 20 major metropolitan regions. The index, calculated every month, follows repeat sales.